アカヒゲホソミドリカスミカメの交尾と産卵の関係

Abstract

The age at which the rice leaf bug, Trigonotylus caelestialium, starts to copulate after adult emergence was determined by mating experiments. Females started to copulate 30 h after emergence and all females copulated after 102 h, when maintained under 16L:8D conditions at 25°C. After copulating once females were individually caged with a male 3, 24, 48 h after the initial copulation to determine if females copulate more than once. Multiple copulations were observed in 17 females among 22 females examined. To determine the effect of multiple mating on the reproductive performance of the bugs, fecundity, longevity and fertility of the eggs laid were investigated under different mating conditions. Newly emerged females were divided into three groups: virgin females, females constantly with a male and females with a male until the first oviposition was observed. There was no significant difference in the preoviposition period and total number of eggs laid between the three female groups. Although the longevity of virgin females was significantly longer than mated females, no significant difference in longevity was observed between the two groups of mated females. The fertility of eggs laid by females constantly with a male and females with a male until the first oviposition was 92.9% and 94.4%, respectively, and was not significantly different. These results suggest that mating(s) during the preoviposition period is sufficient for reproduction of the female rice leaf bug.